This white paper focuses on using thermal transient measurement techniques combined with power cycling for the evaluation of degradation in die attach material in power semiconductors, specifically IGBTs. It features test and supporting thermal simulation methodology alongside example results from IGBTs tested over 1000’s operational cycles to point of failure. Results and analysis are presented on identifying degradation development before actual failure to illustrate how these methods can be used to determine useful life of devices relating to other failure modes beside detailed studies in support of die attach material selection.